26Al and Liquid Water Environments in Comets

  • M. Podolak
  • D. Prialnik


Whether liquid water can exist in comets depends on the realtive rates of heating and cooling in the interior. Historically, as our understanding of the relevant processes has improved, conclusions have changed. We review the different computations performed in the past, and discuss the effects of heating by radioactives in general, 26Al in particular, and the phase transition from amorphous to crystalline ice. Cooling mechanisms include heat conduction through the ice, and heat carried by the flow of gas through the porous nucleus. The most recent models show that conditions for producing liquid water can be achieved only under rather contrived circumstances.


Liquid Water Cometary Nucleus Asymptotic Giant Branch Oort Cloud Thermal Diffusion Coefficient 
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© Springer Science+Business Media New York 1997

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  • M. Podolak
  • D. Prialnik

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